Spectral lineshape determination by self-deconvolution.

A data-processing method is described for the determination of spectral lineshapes using deconvolution of the data with an initial estimate of the same spectrum, referred to as self-deconvolution. The method is demonstrated using computer-simulation studies and experimental data, and is shown to accurately determine amplitude and phase lineshape distortions which may be caused by field inhomogeneity and gradient eddy-current effects. The results indicate that the method is robust in the presence of noise and errors in the initial spectral estimate. Once the spectral lineshape is determined it can be incorporated into a parametric spectral-analysis procedure, thereby reducing the number of parameters to be determined and improving the accuracy of the fit. A proposed application of the method is for spatially resolved in vivo NMR studies where local susceptibility effects and gradient eddy-current effects cause significant deviation of the spectral lineshape from a Lorentzian lineshape.